It is known to use treatment systems in order to reduce polluting vehicle emissions. Emission standards are set in many countries in order to limit the amount of pollutants released into the environment. At present, in order to fulfill the European and USA requirements, selective catalytic reduction and diesel particulate filters working in conjunction with one another are required. Both the selective catalytic reduction and diesel particulate filters take up valuable space in a vehicle.
Diesel particulate filters (DPFs) primarily filter soot, which can be burnt off the filter. However, they also filter ash from the emissions, dust from incoming air and fragments from the vehicle engine, which cannot be burnt off. It is therefore usually a requirement of a DPF in a commercial vehicle that it must have a removable cover so access for cleaning can be gained. In smaller, domestic vehicles, a DPF is designed to last the lifetime of the vehicle, so does not require a removable cover.
What is required is a method of treating exhaust emissions to the current standards that takes up a relatively small amount of space as possible in a vehicle. Access to filters may also be required.